William p



(No Model.)

W. P. ELLIOTT.

- GATE.

' No. 368,522. Patented Aug. 1.6, 1887.

n. PETERS. Plmm-Lnnugmpner, wlshingw' n. c.

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Unirse drains Partnr tribe.

VILLIAM P. ELLIOTT, OF CHICAGO, ILLINOIS.

GATE.

SPECIFICATION forming part of Letters Patent No. 368,522, dated August16, 1887.

Application filed June 16, 1887. Serial No. 241,516; (No model.)

To aZZ whom it may concern.-

Be it known that l, VILLIAM P. ELLIOTT, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Gates; and l herebydeclare the following to be a full, clear,v and exact description of thesame.

My invention relates to an improvement in the class of gates mostcommonly employed to form the barriers at railroad-crossings, whichbarriers are produced by vertically-swinging y bars or arms on posts,two of which arms, ar-

ranged to be swung toward and from each other, ordinarily constitute agate, and they are actuated to be raised and lowered by fluidpressure,preferably air-pressure, exerted from a pump against piston orcollapsible receiver mechanism connected with the gate-bars.

In gates of the class named difficulty is enr countered in producinguniform or simultaneous action of the members forming each pair ofgate-bars, owing to differences in the amount of friction in themovements of the respective arms, or to other differences in theconstruction of the mechanisms ofthe two, and also and particularly tothe force of the wind, which, when it blows in the direction of theplane of movement of the bars,tends to hasten the descent or rise ofone, while it impedes that of the other.

Various means have been devised for overcoming the difficulty referredto,involving the mechanical tying together below the surface of theground or overhead of the gate-bars forming a pair,or the arrangement ofthe tluidpressure mechanism in a manner to produce resistance inoperating the bars in one direction-t. c., either to raise or lowerthemMby the fluid introduced intothe pressure mech anism in operatingthem in the opposite direction.

I desire,byI means of my invention,to avoid the mechanical tyingtogether in contradistinction to arranging the fluid-pressure mechanism,as last aforesaid, of the gate-bars, and the objections attending suchtying mechanism, and my presentinvention is in the nature of animprovementin the said lastnamed manner of producing simultaneousmovement of the gate-bars.

It is my object to provide a very simple and effective mechanism for thepurpose, and to this end my invention consists in the generalconstruction of my improvement, as also in details of construction andcombinations of parts, all as hereinafter more fully set forth.

The drawingis a broken diagrammatic View of a gate provided with myimprovements,and having the sides of the hollow posts removed to displaythe mechanism within them.

A and Aare hollow gate-posts to be located at opposite sides of a streetor railway crossing on the same side of a railway-track. The postscarry, respectively, the swinging barsB and B, supported on therock-shafts r and r', carrying each a double bifurcated pulleysection,C, of the construction set forth in the joint application of A. Farrarand myself for an improvement in gates, Serial No. 225,957, filedJanuary 31, 1887. On opposite sides of theaxis of each gate-bar,withinthe post carrying it, are cylinders-D and E in the post A and D and E inthe post AMeach communicating eontrollably from its upper end by a pipe,t, with an air-pump. (Not shown.) Vithin the cylinders, which are closedat both ends,V are pistons F, the rods F of which project through andbeyond the lower ends of the cylinders, where the latter are providedwith narrow eX- tensions or nipples q, forming guides for the rods,which fit them so closely as to cause the lubricatingoil to affordsufficiently eective packing to prevent escape of the air to an extentthat will materially affect the operation of my improvement, hereinafterdescribed. If

desired or required, however, suitable stuffing-boxes may be provided.The lower ends of the rods have cross-heads p secured to them, fromwhich they are connected by chains o or other suitable means with thesegments, all as described in the aforesaid joint application, fromwhich the mechanism thus far described differs only in construction ofthe cylinders, whereby they are closed at both ends from communicationwith the surrounding atmos phere.

The piston-rods of the cylinders D and E are connected together fromtheir cross-heads by a cable, n, or equivalent means, passing aroundpulleys fm, supported in the post A, near its base, below the lowerlimit of play of ICO the rods, and preferably of the kind movable onanti-friction rollers, and the piston-rods of the cylinders D' and E aresimilarly connected by a chain, n', 'or equivalent means, passing aroundpulleys m', supported and constructed like the pulleys m.

The cylinder D in the postA communicates from its lower end through apipe, Z, embedded between the posts in the ground, as shown, with thecorresponding end of the cylinder E' in the post A', and the cylinderDin the post A' communicates similarly, through a pipe, Z', with thecylinder E in the post A.

As shown in the drawing, the gate-bars are raised, the parts of themechanism being in the positions to which they are moved by raising thebars. To lower them, the cylinders E and E' are caused to communicatethrough their pipes t with the air-pump, and the cylinders D and Dthrough their pipes t' with the open air. By operating the pump, air iscompressed against the upper sides of the pistons in the first-namedcylinders, forcing them down, and consequently lowering the gate-bars,and the air previously introduced below the pistons in the cylinders Eand E'in raising'the arms is forced by the pressure of the pistonstherein through the pipes t and t against the under sides of the pistonsin the cylinders D' and D, thereby forcing them upward, and causing thepiston in the cylinder D', owing to its connection with that in thecylinder E', to pull the last-named piston down, and the piston in thecylinder D, owing to its connection with that in the cylinder E', topull that piston down. If, therefore, to illustrate, the barB works moreeasily than the bar B', or, say, while the bars are being lowered thewind is blowing in the direction of the falling movement of the bar B,the tendency will be for the lastnamed bar to fall faster than the barB', but the pressure of the exhaust-air from the cylinder E against thepiston in the cylinder D' will meet at the latter with the resistance ofthe force impeding the descent of the bar B', and as it cannot enter thecylinder D faster (or much faster) than the rise of the piston thereinwill permit, the piston in the cylinder E cannot fall faster than thatin the cylinder D rises; hence the two bars must fall simultaneously,or, allowing for leakage and elasticity of the air, almostsimultaneously. Ihe pressure from the cylinder E' by the descent of itspiston against that of the cylinder D to raise it obviously increasesthe force which operates against the piston in the cylinder D to raiseit. The effect is the same whichever of the gate-bars is impeded orhastened in either of its movements.

The piston-heads are preferably, to insure the prevention of. leakagearound them, of the double form shown, and the lower ends of thecylinders are provided with plugs 7c, to permit the discharge of thefluid contents below the pistons when desired.

The lookin g mechanism G illustrated is substantially like that shownand described in Letters Patent No. 855,518, dated January 4, 1887, andis not therefore described in detail in the present connection. I preferto support the diaphragm devices h in the posts, as shown, sufficientlyhigh to avoid the possibility of access to them of water, unless, ofcourse, under very extraordinary circumstances, and when so supportedthe latch portion g is rigidly connected with the diaphragm by means ofan iron rod, f.

As it is desirable to provide for the locking of the gate-bars in theirraised positions at different angles, I provide two hooks orshoulders,e, on the latch portion g, either of which may be caused to engage withthe adjacent cross-head, depending upon the angle at which it is desiredthat the bar shall extend when in its raised condition. v

What I claim as new, and desire to secure by Letters Patent, is

l. In a gate having swinging bars on posts and actuated byfluid-pressure, the combination, with the bars, of two cylinders at eachpost, having their pistons connected together, and with the bar onopposite sides of its axis, conduits connecting the cylinders with thepressureesupply, and conduits connecting them with cach other in pairsfrom one post to another, substantially as and for the purpose setforth.

2. In a gate having swinging bars B and B on posts A and A' and actuatedby duid-pressure, the combination, with the bars, of cylinders D and Eat the post A, having their pistons connected together, and with the barB on opposite sides of its axis, cylinders E' and D' at the post A',having their pistons connected together, and with the bar B on oppositesides o'f its axis, conduitsl and Z', leading,

IOO

respectively, from corresponding sides of the pistons in the cylinders Dand E to the same sides of the pistons in the cylinders E and D', toafford communication between the cylinders D and E' and E and D', andconduits leading from the cylinders to the airpressure supply on theopposite sides of their pistons, substantially as described. i

WILLIAM l?. ELLIOTT. In presence of WM. R. SITLER, CHARLES W FLANAGAN.

